Shuttle car



A. l.. LEE

SHUTTLE CAR June 3, 1952 /NvENTO/Q ARTHUR L. LEF. BY

3 Sheets-Sheet 1 Fil'ed Dec. 3.' '1947 A. L. LEE

SHUTTLE CAR June 3, 1952 3 Sheets-Sheet 2 Filed Dec. 3. 1947 ARTHUR 1LEE BY ATTY.

June 3, 1952 A, L, LEE '2,599,061

SHUTTLE CAR Filed Dec. 5, 1947 v3 Sheets-Sheet 5 lNVENToR;

ARTHUR' L LEE BY HTT'Y Patented June 3, 1952 SHUTTLE CAR Arthur L. Lee,Upper Arlington, Ohio, assigner to The Jeffrey Manufacturing Company, acorporation of Ohio Application December 3, 1947, Serial No. 789,384

This invention relates to a shuttle` car, and an object of the inventionis to provide an improved shuttle car in which the load carryingcapacity is very high for any predetermined height, length and width. i

A more specific object of the invention is to provide a shuttle car inwhich there are four power driven steerable wheels provided withimproved drive gearing for driving the wheels in pairs near oppositeends of the vehicle through drive gearing including av worm typediierential which makes for a high ratio of body width to tread or wheelgage.

Another object of the invention is to provide an improved shuttle car inwhich the load carrying capacity is made relatively great vfor any givendimensions, in that substantially all ofthe driving motors for thevarious motor driven devices are located laterally of a conveyer whichforms the bottom of the load carrying body and extends through a boomadjacent the discharge end thereof.

Still another object of the invention is to provide an improved relationof parts in a shuttle car which contributes to high capacity involvingthe locating of an operators station adjacent and to one side of thedischarge boom of the shuttle car, there being a, pair of operatingmotors adjacent the other side of said boom, below which is a cable reelmounted for rotation on an upright axis and driven by one of saidmotors, the reel extending at least in part below the discharge boom.

Other objects of the invention .will appear hereinafter, the novelfeatures and combinations being set forth in the appended claims.

l'n the accompanying drawings,

Fig. l is a plan view of a shuttle car embodying the features of myinvention, with parts broken away;

Fig. 2 is a side elevational view of said shuttle car;

Fig. 3 is a side elevational view showing particularly the discharge end'and .discharge boom and associated cable reel of the shuttle car;

Fig. 4 is a detailed sectional view showing the worm driven differentialof the drive gearing between one of the wheel driving motors anda pairof steerable drive wheels;

Fig. 5 is a detailed sectional'view showing a portion of the drivegearing for the cable reel;

and

Fig. 6 is a sectional elevational view of one of the wheel assemblies.-

Referring particularly to Figs. 1 and 2 of the drawings it will be seenthat the shuttle car of 6 Claims. (Cl. 214-8336) my invention involves aload carrying body I0 which is mounted upon a, main frame, one of theside members of which is seen at II in Fig. 4 of the drawings. The loadcarrying body II) includes laterally spaced sloping side walls l2 and I3provided with wheel receiving wells I4 and I 5 and an end wall I6, saidwalls I2, I3 and I6 all sloping inwardly and downwardly to a bottomplate I1 which constitutes the bottom of the open top load carrying bodyI0 and forms the material supporting plate of a longitudinally extendingendless conveyer I8. Conveyor I8 includes a driving head shaft I9 and atail or discharge shaft 20 between which a pair of endless chains 2Irun. Extending between the chains 2| is ra plurality of conveyer ights22 which in traveling along their` upper run or over the bottom plateI'I convey coal or other material in the body I0 rearwardly along saidplate I'I, discharging it over the tail shaft 20.

Adjacent the rear the body I0 includes a discharge boom 23 which isformed by a portion of the bottom plate Il which is preferably severedwith respect to the adjoining portion which is rigidly att/ached to themain frame of the vehicle, the boom 23 being preferably but notnecessarily pivotally mounted upon a horizontal axis by pivot means 24and being adjustable so as to raise and lower the discharge position ofthe rear end of said boom 23 by means of a hydraulic jack 25. Inaddition to the bottom plate II the boom 23 also includes substantiallyvertical side walls 26 and 2l. The tail shaft 20 is, of course, actuallycarried at the rear end of the boom 23 and the working run of theconveyer I8 conveying material rearwardly travels successively over thebottom of the main body portion I0 and communicating boom 23, both ofwhich constitute load carrying portions of the shuttle car.

In the preferred form of my invention the shuttle car includes two pairsof power driven steerable wheel assemblies, there being a pair of wheelassemblies 28 and 29 near the front end of the vehicle Within the WellsI4 and I5, respectively. The wheel assemblies 28 and 29 are of similarconstruction, except that one of them is provided with a differential,the other, of course, eliminating the differential, this feature beingbroadly similar to that disclosed and claimed in my application SerialNo. 518,810, led January 19, 1944, entitled Shuttle Car, now Patent No.2,457,569, dated December 28, 1948; the actual drive gearing, however,from the differential to the individual wheels being different ashereinafter explained.

Near the rear end of the shuttle car there is `bottom plate be just aswide' as'po'ssible.

3 Y a second pair of power driven steerable wheel assemblies 3|) and 3|which are similar to wheel assemblies 28 and 29. The wheel assemblies28v Vtread of the wheels 23, 29, 3|) and 3| and for 4 any givenV lengthof the vehicle it is;` of= coursef desirable that the body lltandtheboom-ZSfbe as wide as possible, particularly adjacent the bottom. Inother words, it fis desirable that the provide a very wide bottom platewhile' retainingA the desirable characteristics of driving the wheelassemblies adjacent opposite ends inpai-rs from a common driving-motorthrough a differential,

it hasY been fou-nd desirable-'to employ. a worm type of differential.AvIn. other'words,r the worm type differential-allows a gneater.widthofVbottom plate-|1101' greater width-of the body AHlfor any given tiretread-v or gage inla drivev of the above general character incorporatingthereatureswhich have been-found particularly desirable. Y Y

"Ilrfe'refore-I drive, the 4Wheel assemblies iii-and 29 froma commonelectric motor 3,4! which is connected telav worm 35 driving V.a wormtype ring gearl '("see Fig. Blof a differential mechanisn38 whichdiferentialmechanism in turn has differentiallyl connected oppositelyAextending Y.dri-'ve shafts'3l` and 38 having` -a common transverse,horizontal axis',f the former of whichk drives a dishedgear69which`-inturn'drives the wheel of the assembly 28T througha Auniversaljoint. The drive from the shaft 31760 thewheel prefer'ablykfollows thedisclosure of` my- Patent No.V 2,381,672, dated August 7,1945, rather'than my said 'Patent' Nif-2,457,569'. Stated another Way,thedrive'which "I prefer to use is essentially ltha'lt `if-'my Patent2,3`8'1,672',`"exc ept the differential 'liasbe'en' modified to lprovidea worm type `diIiereta.l,A it having" been found thatt'hs allows awideiframeto befplacedv between theY wheel 'asSemblisforYany given'gage, treador distance betweerisaid' Wheel assemblies.

pointing 'out certain important' 'fele'ments andV relations 'which"contribute to the" improvement herein claimed. The'gearing from theVdrive Y Shaft 31130 the'whel' Of the assembly-Za'eld's a doubleuniversal j o int"|8 anda large"internally toothed gear 69', the axis'ofwhich' is sub- Y stantially along'the axis ofrotatio'n'of thewhe'el ofassembly 8.` I t 'is thus evident that the common axis vofj'the twodrive shafts 'Bland 38v is vappreciably',spaced from'v the axisjofrotation' of the wheel Voffthe 'assembly 28 and, as illustrated in thedrawings; is be1oW'it whichv is im" portant since the Vshaft V38 is inalignment with a shaftl'42 extending' towheel assembly 29V on;

the opposite side of thevehicle. It is desirable in the interest of highcapacity that this shaft 42 be as low, as ApossibleY since it ispreferably below Vthe bottom plate 5 I 1.

Itis furthermoreto beinoted, particularly 'by reference to Figs. 4 ,and6offthe drawings, that the axis ofthe worm 35"-is spaced-from-'thecomassembly; is Yillustrated in:

mon axis of the shafts 31, 38 and 42 and this spacing is in the samedirection as the spacing between the common axis of said shafts 3l, 38and 42 and the axis of rotation of the wheel of the assembly 28.Specifically the axis of worm 35 is appreciably below the common axis ofshafts A3l, 38an`d 42. 1 The importance of this spacing is describedhereinafter.'

The differential mechanism 36V is connected to the main frame member onone side thereof laterally outside the dimensions of said main frame andof said load carrying body lo. Likewise,Y the adjacent driving motorl 34which drives the f worin- 35 vis-locatedoutside the lateral confines ofthe mainframe and laterally ofthe adjacentside wall=|2of said body It.Motor 34 is located longitudinally beyond the periphery of the' adjacentwheel 34, to the end that said wheel 28 in swinging during its steeringoperation will nothit said motor 34.' Th'us the motor V34'does notVrestrict Ithe angle throughV which? stef-rable wheelA 28'can swingtoefiec't steering'. Said'motor 34 is connected to theworm'35 throughi af splined telescoping drive shaft 39 anda pair of universal joints 40and 4| ,one at each end thereof:J The positioningof vthe motor 34- aswellras the differential casing `36 laterally .ofthe 'main frame memberlglobvi'ously positions bothr-of themv entirely laterally/ori to theside-ofthe. conveyor i8, -as a consequence ofwhioh the bottom plate maybe positioned very'low in the body. I'D; or, in other words, quite closeto the mine floor'which contributes to the high overall capacity-'of'said body I0. The twofwheellassemblies28'and-29am interconnectedbycross shaft 42 which is splined tolthe aforementionedfshaft 38 andWhichffdrives thev Wheel assembly 29,-.' *f CrossjshaftAZris below, theplate v| and-consequently below` the vupperv run ofthe conveyerflzandjis preferably between the upper and lowerI runs thereof, similar:tothe arrangement in the shuttle car disclosedi'n my Patent No.2,457,569. Y

The Vsteerabley Wheel assemblies '30 'anfdr 3| tare also driven as apair froma common 'electric driving-'motor 43 through appropriateuniversal -Ijoints and splined drive fshaft IMI-"which drives-aJ worm of-a differentialv mechanism* adjacent thewheel assembly 3|V which" is"sim-ilarl to` the "assembly above described inf 'association with Ithe'Wheelv assembly, 28; Wheel assemblies-30 'and' 3'I'are in turn drivenfromV the, oppositelyl extending shafts' of the above mentioneddiiferentiaLf'the former through a cross shaft 45 which is generallyisimilar-'to crossshafti42'- andi. extends betw'eenJ-the upper and lowerrunsf 'offthe conveyor "|'8 'and 'below the plate |'|.A Here'again it is.to be particularly noted thatrboththe .differential ofth'e drivingwheel assemblies 3|ly and `3| 'andth'emtor A43' are positioned laterallyof the conveyer |8"anf4 laterally. of the -side main framemembercorrespending to main frame member thougho'nl theoppositeside'Y of-theunitg -Itis also to be noted that motor43=2islongitudinallybeyondthe cated `1mgaudimat-'fyi:inve/annif thereof-anu'thus Y longitudinally between the wheel assemblies 29,n

ad3l.

All of the Wheel asseiiibliesf 28,529.9,3 130i and'3'l' are' alsovpreferablysteerable-asi Well' asL power Asiabevef-set rorthfthe axis-ofthe Ywornifst is spaced an appreciable distance from the axis ofrotation of the wheel of assembly 28 and, specifically, is appreciablybelow it. It is likewise appreciably spaced from the common axis ofrotation of shafts 31, 38and 42 and is also appreciably ,below thiscommon axis, which axis itself is appreciably below the axis of rotationof the wheel of the assembly 28.

As a consequence of this structure the axis of the drive shaft 39 whichinterconnects the motor 34 and the worm 35 is spaced an appreciabledistance from and below the axis of rotation of the wheel of theassembly 28. Therefore the wheel of assembly 28 in effecting a steeringoperation can swing through a greater angle before striking the shaft 39than would be possible if the axis of said shaft 39 intersected the axisof rotation of the wheel of assembly 28. In other words, consideringFig. 2 of the drawings, if the axis of the shaft 39 extended through thecenter of the wheel of assembly 28 it is obvious that as the rear end ofthe wheel of said assembly 28 was swung toward the shaft 39 it wouldstrike it sooner than it would with the shaft 39 in the lowered positionillustrated. This, of course, is due to the curvature of the peripheryof the wheel of said assembly 28.

Therefore, the worm drive for the differential mechanism 38 contributesin two particulars, both of which tend to increase the capacity of theload carrying body without diminishing the steerability of the unit.First, of all, this unit yactually requires a less axial dimensionbetween the main frame side member I| and the face of the gear 69 whichallows a somewhat wider load carrying body for the same wheel gauge.Secondly, it increases the distance between the axis of rotation of thesteerable wheel and the axis of the connecting drive shaft 39 betweenthe driving motor 34 and the worm 35 which allows a smaller dimensionbetween a vertical plane through the axis of the worm 35 and a verticalplane through the wheel of assembly 28, when it is in its straight-aheadposition, for the same amount of steering swinging movement of the wheelof assembly 28, as compared with the drive arrangement, for example, ofmy Patent No. 2,457,569 in which a beveled pinion and ring gear 51, 59is provided and in which the axis of the pinion gear 51 is substantiallyalong the common axis of the shafts 63 and 84 which are generallycomparable with the shafts 31 and 38 of this application.V

While the above relation of parts has been described particularly invconnection with the driving motor 34 and associated wheel assembly 28,it is, of course, understood that the same fundamental relation existsbetween the motor 43, the shaft 44 and the wheel I'assembly 3 I. In thisconnection it is to be noted, however, that motor 43 is located betweenthe two wheel assemblies 29 and 3|. Stated another way, motor 43 islongitudinally inwardly of the wheel assembly 3I while the motor 34 islongitudinally outwardly of the wheel assembly 28.

The important relation of the parts above described in detail whichprovides for the greater capacity of the body I0 without restricting thesteering, 0r, in other words, without enlarging the circle through whichthe shuttle car will travel, is even of greater importance in connectionwith the motor 43, shaft and wheel assembly 3| than with the motor 34,shaft 39 and wheel assembly 28 for the following reason. In acompensating type of steering mechanism which is generally employed invehicles, including this one, .as disclosed -in detail in myapplication, Se-

rial No. 771,542, above mentioned, when the vehicle has its steeringwheels turned the two wheels of each pair ofsteerable wheels travelthrough circles of unequal radii, and the inner wheelnecessarily travelsthrough the circle having a smaller radius than the radius of travel ofthe outer wheel. As a consequence the steering wheels .are so tiedtogether that when they are turned the inwardly turned wheel or wheelsturn or swing through a greater angle than the outwardly turned wheel orwheels. As a consequence of the fact that the wheel of assembly 3| tendsto strike Vits driving shaft 44 due to inward swinging of the Wheelassembly 3|, it would normally tend to strike said shaft 44 before thewheel of assembly 28 will strike its shaft 39 since the wheel ofassembly 28 tends to strike the shaft 39 by outward rather than inwardswinging movement. This all assumes, of course, that the clearancebetween wheel 3| and shaft 44 is the same as the clearance between wheel28 and shaft 39 when said wheels are in their straight-ahead ornon-turning position. Actually therefore the shaft 44 is the truelimiting element determining the maximum swinging of the steerablewheels of the assemblies 28, 29, 30 and 3| under the conditions assumed.This makes it possible to swing the shaft 39 outwardly, as viewed inplan and as illustrated in Fig. 1 of the drawings, slightly more thanthe shaft 44.

This four wheel steering mechanism is controlled by a steering wheel 41adjacent an operators station 48 which is located near the rear of theunit and on one side of the boom 23 in a pocket which is formed by thereduced width of said boom 23 ascompared with the overall width of thebody IIJ, being located directly to the rear of the wheel assembly 30.As disclosed in said application Serial No. 771,542, the wheel 41controls a hydraulic valve 49 which in turn controls a motor drivensteering gear 50 having a swinging arm connected to the steeringmechanism 46. Since the structural details of the steering arrangementper se are not a feature of the invention here claimed but are claimedonly in cornbination, a detailed description thereof is believedunnecessary in view of the disclosure there- 0f in my application SerialNo. 771,542.

The drive shaft I9 of vconveyer I8 is driven from an electric motor 5|which is positioned outside or laterally to one side of the conveyer I8and main frame of the vehicle and is connected to the shaft I9 throughgearing including a splined drive shaft and universal joints Ydesignatedas a whole by the reference character 52 and reduction gearing 53 whichis also located laterally of said main frame and said conveyer I 8.

Adjacent the rear of the vehicle and on the opposite side of the boom 23from that where the operators station 48 is located and rearwardly ofthe driving and steering wheel 3| on said opposite side of the vehiclethere is an electric motor 54 also located laterally of the conveyer I8and of the boom 23 lsaid motor 54 driving a hydraulic pump 55 throughgearing including a splined drive shaft and universal joints designatedgenerally 56. The pump 55 is also located laterally of the conveyer I8and boom 23. Said pump 55 is the source of hydraulic pressure for ahydraulic control system not disclosed, part of which includes thecontrol valve 49 and steering gear 50, another part of which includesthe hydraulic jack 25.

Adjacent said motor 54 and pump 55 is another which, of course, is onelimiting factor.

7 it may. be hydraulic, which motor y51 drives an electric cablereel'iiY :through gearing which in# cludes a generally'upright shaft 5.9(see Fig. 5) having ar sprocket 69 which meshes with an endless rollerchain 6I. anchored to a circular shrouding guide 62 which is rigidlyattached to the top plate of the reel 58.

As clearly illustrated in Figs. 1 and 3 of Vthe drawings, the electricVcable reel is mounted for rotation on a generally vertical or uprightaxis and a substantial portion thereof extends below the boom 23' andconveyer i8. This makes possible the employment of a relatively largereel which can handle a great length of electric-cable 63 which isreeled thereon, While permitting a relatively wide conveyer 'i8 in theinterest .'Of high capacity, as above set forth. This construction ofthe cable reel also does not interfere with the lowV overall height ofthe shuttle car The cable 63 is adapted to extend rearwardly from thevehicle as illustrated particularly in Fig. 3 of the drawings, or it maybe extended forwardly by being reeved around Va guide sheave or roller64. A ventilated resistor box 65 is provided-on the rear corner ofV thevehicle above the cable vreel 58, being carried. by anv adjacent platemember of the body i0.

From the above descriptioniit is evident that a shuttle car has beenproduced which includes the desirable features of fourV wheel drive Aandfour wheel. steer in the preferred and? most specic embodiment of theinvention. In Yaddition, a number of expediente have been employed toproduce highload carrying capacity for any given dimensions.: First ofall, while preserving the desirable feature of driving pairs of wheelson opposite` sides of the vehicle at one end Yfrom a common motorthrough a diiferential, gearing is employed involving a `wormdri'vedifferential which allows for a relatively wide conveyer FE or, in otherwords, a relatively wide bottom load carrying body. Also all ofthe'dri-ving motors for the various. devicesl are mounted' on they bodyor main frame and located laterally outwardly of the conveyer t8, noneof; said motors being positi'one'd, even in part, between the`lateralextremi-A ties of said conveyer. This includes the' twoinotors34 and i3 which Vdrive the wheel assemblies 25, 29, 3a and Si, the motor5I which drivesthe the conveyer 1.8, and the motor 54 which dri-'ves thehydraulic pump 55', said hydraulic pumpf 55 being similarly located. Italso includesthe motor 57 which drives the electric cablereel' 58; Inaddition, the positioning of the electric cable reel 58; on yan uprightaxis, a portion' ofit` being adjacent one side of'the discharge booln23anda portion of it extending directly beneathsaiddischarge boom and theconveyer I-8 as it trayels thereover, cio-operates to produce a compactarrangement contributing towardsthe desiredi end of high loadA carryingcapacity.

It is, of course,.obvious that within the broad scope of my invention;as expressed in some of the claims, one pair of wheel assemblies; suchasthe wheel assemblies 28! and- 2:3, may bepower driven with or without'.steering, the-other wheel assemblies, such. aszwheelassemblies 30 and'24,

may be only steering` wheels, the driving mecha--Y sincethe particularforma'of steeringmehansiii 75" illustrated per se is not a signincantfeature of the invention herein claimed, it being claimed in mycompanion application Ser. No. 771,542.

It may also be mentioned that the operators station 43 provides for theVoperator to sit on ap'- pr'opriate seats and selectively face eitherdirection, depending upon the direction of travel of the shuttle car. Itmay also be mentioned that 'the space laterally of the conveyer I8 oroutside the receiving portion of the open top material carrying body I9and within the lateral confines of the body lil Vvis highly utilized. Toillustrate, .motor V3e is located forwardly of the wheel as'- sembly 2Band laterally 'of the conveyer I8 but within the adjacent lateralextremity of the .body I0. .Motor 5l is similarly located on theopposite 'side of the vehicle ahead of wheel assembly 29. Motor 43 islocated laterally of the conveyer I t within the lateral boundary of'the body i0 and between the wheel assemblies 2a and 3%. A controllerbox 65 is located on the opposite side of the vehicle and between thewheel assemblies 2t and 30, also within the lateral confines of the bodyI 0 and laterally of conveyer l-B.- The operators station including theoperators controls is'located in the area at one side of the boom 23land rearwardly of the wheel assembly all, extending to the adjacentlateral edgel of the body l0. On the oppositeY sideofV thel boom 23 arethe motors E@ and 51 and the pump 55 together with the resistor box t5.Below thesel units is a portion of the reel 58, a portion of which reelalso extends directly below the boom 23. As previously mentioned, boom23 may be vertically adjusted about a horizontalv pivotal axis but, ofcourse, motors ed and 5l as well as cab-le 'reel 58 do not move with itVbut 'are carried ,by the body if! or associatedmembers connected to themain frame of the vehicle.

Obviously those skilled in the art. may make various changes in thedetails and arrangement of partsy withoutv departingv from the spiritand scope of the invention as dened by the claims hereto appended, and Itherefore wish not to be restricted to the precise construction` hereindiscloseda Having thus described and shown an embodiment of myinvention, what I desire to secure by Letters; Patent of the UnitedStates' is:

1. A shuttlercar including a mainframe carrying1 an open'top rec'eptabletypeV body adapted to carry loose coal, a conveyer in the bottom of saidbody operable to remove the loose'coaltherefrom, foursteerable wheelssupporting said` body, means for driving said wheels in pairs atopposite ends ofsaidl vehicle includingga separate driving. motorforeach. pair of wheels at each end of 'said car, gearing connectingeach motorv with a pair of wheels at one end of the car, each. saidgearing including a` difierentialzhavnga worm type ring' gear drivenfrom' a motori throughv a driving worm' located below and meshing withsaid: ring' gear means mounting each said differential an'didrivingmotor laterally outside said main frame andv nearone of said wheels witheachv motor located longitudinally beyond tneperiphery of theadijaoen't. wheel, each saidl gearing also including a drive' shaftinterconnecting theV adjacent motor and driving worm 'andextendinglongitudinally offsaidrnain` frame and into-thepath ofsteeringv swinging movement of the' adjacent steerable wheel-if 'saidswinging movement were unlimited, andy shaft driving means-,extending inopposite directions from each said' differential, one ot said .ingincluding a diierential having a worm type ring gear driven from saidmotor through a driving worm located below and meshing with said ringgear, said differential and driving motor being located outside saidmain frame and near and longitudinally beyond one of said wheels, adrive f shaft between said motor and Worm in the path of swingingmovement of said one near wheel, and shaft driving means extending inopposite directions from said differential, one of said shaft drivingmeans extending laterally across said main frame to a position adjacentone of said Wheels.

3. A shuttle car including an open top load carrying body having adischarge boom at one end, conveyer means forming the bottom of saidbody and extending through said discharge boom and adapted to dischargematerial therefrom, an electric cable reel, driving motor meanstherefor, and means mounting said cable reel for rotation on an uprightaxis and positioning it at least in part directly below said conveyermeans and below said discharge boom.

4. A shuttle car including a load carrying body, a discharge boomextending from one end of said body, a continuous conveyer in the bottomof said body extending through said boom and adapted to dischargematerial therefrom, an operators station located adjacent said boom onone side thereof, a cable reel adjacent the boom on the other sidethereof, means mounting said reel for rotation on an upright axis, atleast part of said reel extending directly beneath said boom, and a pairof motors adjacent said boom and said reel, one of said motorsconstituting the operating motor for said reel.

5. A shuttle car including a load carrying body, a discharge boomextending from one end of said body, a continuous conveyer in the bottomof said body extending through said boom and adapted to -dischargematerial therefrom, an operators station located adjacent said boom onone side thereof, a cable reel adjacent the boom on the other sidethereof, means mounting said reel for rotation on an upright axis,atleast part of said reel extending directly beneath said boom, and apair of motors adjacent said boom and said reel.

6. A shuttle car including a main frame, an open top receptacle typebody thereon adapted to carry loose coal, a conveyer in the bottom ofsaid body operable to remove the loose coal therefrom, four steerablewheels supporting said frame and body, and means to drive said Wheels inpairs at opposite ends of said vehicle including a separate drivingmotor at each end of said car, gearing connecting each motor with thepair of wheels at the adjacent end of the car, each said gearingincluding a differential driven from a motor and located outside saidmain frame and near one of said wheels, shaft driving means extending inopposite directions from said differential, one of said shaft drivingmeans extending laterally across said main frame to one wheel, anduniversal joint drive means extending on a generally horizontal axis andconnecting one of said differential shaft driving means to the wheelnear said differential.

ARTHUR L.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,036,660 Lindsay Aug. 27, 19121,203,390 Noble Oct. 31, 1916 1,364,398 Martin et al Jan. 4, 19211,763,424 Duncan June 10, 1930 1,810,194 Weaver June 16, 1931 1,828,751Shelburne Oct. 27, 1931 1,891,562 Levin Dec. 20, 1932 2,225,185 SloaneDec. 17, V1940 2,274,313 Whaley Feb. 24, 1942 2,317,623 Lee Apr. 27,1943 2,325,731 Arentzen et al. Aug. 3, 1943 2,357,742 Jeffrey Sept. 5,1944 2,359,123 Krapf Sept. 26, 1944 2,381,672 Lee Aug. 7, 1945 2,399,619Beck May 7, 1946 2,426,980 Ball Sept. 9, 1947 2,457,569

Lee Dec. 28, 1948

